Electric motors are incorporated increasingly in modern motor vehicles. Here, they are used in particular as drive motors that are fully integrated in the drive chain or are used in hybrid applications, for example as starter generators. Here, both separately excited or permanently excited synchronous machines as well as asynchronous machines are used.
In particular, internal rotor motors up to approximately 20 kW are also used. The casings of such motors are often cooled by coolant. A casing of this type is known for example from DE 10 2009 031 467 A1.
Generally, the casing has a number of functions: it is intended to support the forces or the torque produced during operation, it can form a coolant jacket for cooling the motor, and it can provide a possibility for fastening other motor compartment assemblies. In order to perform these functions and for reasons of EMC protection, motor casings are fabricated from metal.